To: Journey North
From: Anne Smrcina
Stellwagen Bank National
Marine Sanctuary
Another sad story in the news, this time from Massachusetts. An adult right whale was found washed up on a Cape Cod beach. The beach is known as Newcomb Hollow Beach in Wellfleet and is part of the Cape Cod National Seashore.
This is the sixth whale death since January and eighth since July 1995 that has been documented -- and it presents a very troubling scenario. In order for a population to grow, births have to outnumber deaths. But since only 9-11 births have been confirmed, the numbers don't portend a happy fate for the species. Other deaths may have also occured, but out of sight of human observers.
This whale was an adult male, #2220 in the right whale catalog (no common name), first seen in Florida in 1992 (he was probably a juvenile when first spotted). He had been seen mainly in the Bay of Fundy over the past few years, and had been spotted in Cape Cod Bay last spring. This whale was found with Canadian lobster gear wrapped around its head and cutting into the rete in the upper mouth (an area of massed blood vessels that may be important in heat exchange). The whale did not have any gear entanglements when last seen last September, so the entanglement has happened over the past five months.
The whale had been dead for quite some time -- it was only a few feet high although it was 44 feet long. When whale researchers did a necropsy (an autopsy on the dead animal) on Monday, they found only skin, blubber and bones. The internal organs and muscles had turned to mush in the decay process. Without muscles, the skeleton had collapsed and the normally rotund animal flattened out. Normally a right whale has a diameter of about 8 feet.
Examination of the carcass and the necropsy revealed that the whale had a major cut parallel to its backbone, starting near its tail flukes and ending up near where its kidneys would be. There were a series of shorter perpendicular cuts (perhaps slice marks from propellers) further up along its body. The animal's skull showed some significant fractures, particularly on the back and where the upper jaw attaches to the skull. As I mentioned earlier, decomposition had made most of the insides indeciferable. Not only could they not study stomach contents, they couldn't even find the stomach. The bones had been pushed around; one earbone and both scapula (shoulder bones in humans) were found in the mouth cavity, another earbone in the baleen.
This Week's Challenge Question
Think back to last week's discussion about whales and cold water temperatures. After reading about the whale's massed blood vessels in the description above, see if you can answer Challenge Question #37:
"How do you think whales maintain body temperature in the ocean environment, where heat loss and hypothermia can be a great problem?"
To respond to this Challenge Question, please follow the instructions at the end of this report.
Enough about dead whales. Now for a few more positive notes. Marilyn Marx of the Center for Coastal Studies and Phil Hamilton from the New England Aquarium went out on a survey cruise Sunday and spotted at least ten right whales in Cape Cod Bay, many of them familiar to researchers. Most were juveniles and young adults. One was a young male, born in 1991, the son of Stripe, that had been seen down in Florida this winter. THIS IS THE FIRST CONFIRMED SIGHTING OF A FLORIDA/GEORGIA WHALE IN NORTHERN WATERS THIS SEASON. So, we've got confirmation on at least one migration. Scientists are not sure where the other whales spent the winter.
The above-mentioned information should answer last week's challenge question. It is believed that the whales spotted this spring (except for this one young male) in Cape Cod Bay were NOT part of the Florida/Georgia contingent, but it is not known where it is that they are coming from. Scientists hope to tag some whales this summer (with satellite tags) to see where they spend the winter months.
Chris Slay reports from Florida that the usual decline in right whale sightings at this time of the year is just not happening this year. They've had sightings every day that they've been able to fly, with multiple sightings on most days (although several days' flights were cancelled because of excessive winds). They still have the three mother-calf pairs that have been milling about off the Florida/Georgia coast. Chris also notes that they are seeing increased numbers of other species in the southern aerial survey area, including several large schools of Atlantic angel sharks, cownose rays, and increased numbers of loggerhead and leatherback sea turtles. He also reports that large masses of cannonball jellyfish have also been visible from the air.
Until next week, this is Anne Smrcina signing off.
How to Respond to Challenge Question # 37:
1. Address an e-mail message to: jn-challenge@learner.org
2. In the Subject Line of your message write: Challenge Question #37
3. In the body of the message, give your answer to this question:
"How do you think whales maintain body temperature in the ocean environment, where heat loss and hypothermia can be a great problem?"
The Next Right Whale Migration Update Will be Posted on March 20, 1996
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